1. Field of the Invention
This invention relates generally to patient dentition stain removal, and particularly concerns methods, materials, and apparatus which may be advantageously utilized in connection with the whitening or bleaching of a patient""s teeth in a dental office.
2. Review of the Relevant Technology
Present conventional dental practice in the United States for effectively changing the inherent color of patient""s teeth basically involves: (1) an in-office teeth whitening procedure that generally requires about one-hour of office time, or (2) in-office preparation of a patient kit with instructions, followed by patient use of the kit in teeth whitening treatments at home of from 1 to 8 hours per day repeated for 2 to 6 weeks.
The in-office teeth whitening procedure usually involves, with a protective rubber dam in place in the patient""s mouth: (1) protectively coating the patient""s gingival tissues; (2) applying to and activating on the teeth to be whitened a hydrogen peroxide or carbamide peroxide gel; and (3) afterwards completing a thorough mouth rinse and removal of the protective coating and rubber dam.
The dentist-prepared kit for patient home-use typically includes a custom-configured patient bleaching tray or mouth-guard formed by a multi-step in-office procedure, a supply of whitening agent such as carbamide peroxide gel, and appropriate instructions for kit home-use by the patient. The typical multi-step dental office procedure utilized for forming the custom patient tooth-whitening mouth-guard or tray for home use is a time-consuming procedure, and typically involves the basic steps of: (1) making conventional alginate impressions of the patient""s maxillary and/or mandibular teeth, (2) casting dentition models using state-of-the-art dental laboratory stone casting material and the alginate impressions, followed by trimming-away of un-needed model material, (3) blocking out on the trimmed cast stone models, using a conventional light-cured or light-activated, acrylic-based resin laboratory block-out gel, those tooth areas to be whitened (often excluding all molar teeth), and (4) vacuum forming a 5-inch by 5-inch sheet of 0.040-inch to 0.080-inch thickness clear plastic resin mouth guard material over each blocked-out and trimmed dental stone model, cooling, removing from model, and suitably trimming above the gingival crest. The whitening mouth guard is then ready for delivery to the patient in the patient home-use whitening kit. As indicated above, home-use of the kit mouth guard and kit-included whitening agent (e.g., carbamide peroxide gel) typically requires 1 to 8-hour bleaching treatments repeated daily over a period that generally is in the range of 2 to 6 weeks depending upon the degree or severity of dentition staining.
I have discovered a novel in-office dental procedure that, when utilized as a replacement for the above-described conventional in-office procedures, obtains equally satisfactory whitening results, realizes a significant reduction of required dentist and patient in-office times, and also effects a substantial reduction in the costs of patient teeth whitening treatments.
The present invention relates to the bleaching of teeth involving the use of conventional or specially adapted dental impression trays in conjunction with a dental impression material, heat and a dental bleaching composition. The impression material provides the ability to form a device that can immediately be used to bleach a patient""s teeth, typically within an in-office procedure, using a conventional dental bleaching composition. The impression materials can be heated by, e.g., microwave energy, resistive heating devices, or a heated fluid in order to accelerate the rate at which the bleaching composition bleaches the patient""s teeth.
A first embodiment of the method aspect of the present invention involves the following steps: (1) applying a dental impression adhesive to the surface of the principal cavity of a conventional (or specially adapted) alginate dental impression tray; (2) optionally applying a dental wax sheet overlay to the surfaces of the patient""s teeth to be whitened; (3) filling the coated principal cavity of the dental impression tray with an unset conventional alginate (or other appropriate) dental impression material; (4) placing the filled dental impression tray into the patient""s mouth and holding it in place a sufficient length of time to set the unset alginate dental impression material and thereby form a patient dentition impression; (5) removing the alginate dental impression tray and included set alginate patient dentition impression, together with the optional retained wax overlay material, if used, from the patient""s mouth; (6) if used, scraping or otherwise removing the retained wax overlay from the alginate patient dentition impression; (7) heating the alginate dental impression tray and included patient alginate dentition impression using any appropriate method to a temperature of at least about 110xc2x0 F.; (8) coating the surfaces of the patient dentition impression corresponding to the patient teeth that are to be whitened with a conventional carbamide peroxide or hydrogen peroxide tooth bleaching gel; (9) placing the heated alginate dental impression tray and included alginate patient dentition impression with carbamide peroxide coating into the patient""s mouth; (10a) if the alginate material is continuously heated, by e.g., resistive heat, holding the tray in place for a desired time period to effect bleaching, while preferably maintaining the temperature above about 110xc2x0 F.; (10b) if the alginate materials is temporarily heated by means of microwave energy, repeating the sequence of steps (7) through (10b); and (11) removing the alginate dental impression tray and included alginate patient dentition impression from the patient""s mouth and thoroughly rinsing the patient""s mouth prior to release of the patient.
In a preferred embodiment, the invention involves electrical resistance heating for heating and maintaining the impression material at the desired temperature. Alternatively, the invention may involve the use of heated fluid to maintain the impression material at the desired temperature. In the case of either electrical or fluid heating, steps (7)-(9) may be performed in any desired order.
These and other objects and features of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter.